Adenosine deaminase activity in bronchoalveolar lavage in Turkish patients with smear negative pulmonary tuberculosis

Diagnostic Accuracy of Interleukin-27 in Bronchoalveolar Lavage Fluids for Pulmonary Tuberculosis

Background

The World Health Organization states that China had 0.9 million cases of tuberculosis in 2017, accounting for 9% of cases globally. Despite a decrease in the incidence and mortality of tuberculosis in China over time, development in choosing the appropriate prevention and control of TB is required.

Purpose

The aim of this study was to evaluate the diagnostic significance of interleukin-27 in bronchoalveolar lavage fluids for pulmonary tuberculosis.

Materials and methods

Eventually, 107 bronchoalveolar lavage fluids from patients were included in this study. The concentrations of interleukin-27 and adenosine deaminase were determined in bronchoalveolar lavage fluids using enzyme-linked immunosorbent assay.

Results

It was found that the concentrations of interleukin-27 in bronchoalveolar lavage fluids of sputum-positive pulmonary tuberculosis group were significantly higher than those in sputum-negative pulmonary tuberculosis, lung cancer, and previous pulmonary tuberculosis groups, respectively (all P<0.001). Interleukin-27 levels in bronchoalveolar lavage fluids could be used for diagnostic purpose for pulmonary tuberculosis, with the cutoff value of 7.867 pg/mL; interleukin-27 had a sensitivity of 68.8% and specificity of 100% for the differential diagnosis of pulmonary tuberculosis (sputum-negative and sputum-positive PTB) from lung cancer. And with the cutoff value of 6.012 pg/mL, IL-27 had sensitivity and specificity of both 100% for the differential diagnosis of PTB from previous PTB. The risk of pulmonary tuberculosis was positively associated with the concentrations of interleukin-27 and adenosine deaminase in bronchoalveolar lavage fluids.

Conclusion

Interleukin-27 in bronchoalveolar lavage fluids is a sensitive and specific biomarker for the differential diagnosis of pulmonary tuberculosis from lung cancer and previous pulmonary tuberculosis.

Serum Adenosine Deaminase Activity in Monitoring Disease Activity and Response to Therapy in Severe Psoriasis

Objectives: Activity of Serum Adenosine Deaminase (ADA), a main enzyme in purine degradation and considered as a marker for non-specific T cell activation, in psoriasis has been investigated in a few studies with conflicting results. Design and Methods: To evaluate the significance of serum ADA activity in psoriasis, and analyze whether ADA activity may be related to disease activity, we performed a prospective study with 38 cases of psoriasis and 24 healthy volunteers. Patients were divided into two groups as cases with local and stable lesions (Group i, n: 20) and severe cases with extensive involvement (Group ii, n: 18). Serum ADA activity was determined by modified Guisti procedure. Results: When taken into consideration of all patients -regardless of the severity of the disease- the mean serum ADA activity of psoriatics did not differ significantly from that of controls (p>0.05). However, it was higher in Group ii than in Group i and healthy controls (respectively p<0.001 and p<0.05). A significant decrease was observed also after therapy only in Group ii (p<0.001). Conclusion: Serum ADA activity may be correlated to the disease activity of severe psoriasis. We suggest that it might be a serologic marker for follow-up of in such cases. It could be used in predicting relapses before clinical findings as well as in deciding to stop or decrease systemic therapies at the right time, which have potential to cause severe systemic side effects when given for a long period. Further studies with larger case populations are required to support our findings.

Diagnostic value of sputum adenosine deaminase (ADA) level in pulmonary tuberculosis

INTRODUCTION

Tuberculosis is still a considerable health problem in many countries. Rapid diagnosis of this disease is important, and adenosine deaminase (ADA) has been used as a diagnostic test. The aim of this study was to assess the diagnostic value of ADA in the sputum of patients with pulmonary tuberculosis.

METHODS

The current study included 40 patients with pulmonary tuberculosis (culture positive, smear ±) and 42 patients with non tuberculosis pulmonary diseases (culture negative). ADA was measured on all of the samples.

RESULTS

The median value of ADA in non-tuberculosis patients was 2.94 (4.2) U/L and 4.01 (6.54) U/L in tuberculosis patients, but this difference was not statistically significant (p=0.100). The cut-off point of 3.1 U/L had a sensitivity of 61% and a specificity of 53%, the cut-off point of 2.81 U/L had a sensitivity of 64% and a specificity of 50% and the cut-off point of 2.78 U/L had a sensitivity of 65% and a specificity of 48%. The positive predictive values for cut-off points of 3.1, 2.81 and 2.78 U/L were 55.7%, 57.44% and 69.23%, respectively. The negative predictive values for the abovementioned cut-off points were 56.75%, 57.14% and 55.88%, respectively.

CONCLUSION

Our results showed that sputum ADA test is neither specific nor sensitive. Because of its low sensitivity and specificity, determination of sputum ADA for the diagnosis of pulmonary tuberculosis is not recommended.

Mechanisms regulating airway nucleotides

In the respiratory system, extracellular nucleotides and nucleosides serve as signaling molecules for a wide spectrum of biological functions regulating airway defenses against infection and toxic material. Their concentrations are controlled by a complex network of cell surface enzymes named ectonucleotidases. This highly integrated metabolic network combines the activities of three dephosphorylating ectonucleotidases, namely nucleoside triphosphate diphosphohydrolases (NTPDases), nucleotide pyrophosphatase/phosphodiesterases (NPPs) and alkaline phosphatases (APs). Extracellular nucleotides are also inter-converted by the transphosphorylating activities of ecto adenylate kinase (ectoAK) and nucleoside diphosphokinase (NDPK). Different cell types use specific combinations of ectonucleotidases to regulate local concentrations of P2 receptor agonists (ATP, UTP, ADP and UDP). In addition, they provide AMP for the activity of ecto 5'-nucleotidase (ecto 5'-NT; CD73), which produces the P1 receptor agonist: adenosine (ADO). Finally, mechanisms are in place to prevent the accumulation of airway ADO, namely adenosine deaminases and nucleoside transporters. This chapter reviews the properties of each enzyme and transporter, and the current knowledge on their distribution and regulation in the airways.

Predictive Role of ADA in Bronchoalveolar Lavage Fluid in Making the Diagnosis of Pulmonary Tuberculosis

Current diagnostic tests for tuberculosis (TB) are time-consuming. The aim of this study was to evaluate the diagnostic usefulness of ADA in bronchoalveolar lavage fluid in patients with pulmonary TB. A cross-sectional study was performed in Yazd, Iran, between 2009 and 2010. Patients suspected of pulmonary TB with negative sputum smear for AFB were included in the study. Mean ADA levels in BAL fluids were measured and compared between study groups. Sixty-three patients were enrolled in the study among which 15 cases had pulmonary TB, 33 had pulmonary diseases other than TB, and 15 subjects with normal bronchoscopy results were considered as controls. Mean ADA levels in BAL fluid were 4.13 ± 2.55, 2.42 ± 1.06, and 1.93 ± 0.88, respectively. This rate was significantly higher in the pulmonary TB group compared to the other two groups (P = 0.001). Using ROC curve with a cut-off value of 3.5 IU/L, the highest sensitivity (57%) and specificity (84%) were obtained in diagnosis of TB. The results showed that although ADA activity in BAL fluid of pulmonary TB patients was higher than those seen in other diseases, a negative test does not rule out pulmonary TB.

Study of adenosine deaminase activity in pulmonary tuberculosis and other common respiratory diseases

Tuberculosis has, in a short span of time, become a major health problem in the third world or developing countries like India. In view of this, a retrospective study was conducted to study Adenosine deaminase activity in serum and pleural fluid in patients affected with Pulmonary Tuberculosis and other common non-tubercular chronic respiratory diseases. The study was carried out on 100 patients suffering from various pulmonary disorders, between January 2002 and August 2002. Thirty-five normal healthy individuals were included as control subjects. ADA estimation was done by sensitive colorimetric method. The study revealed that the serum ADA activity was higher in patients of tuberculous pulmonary and pleural diseases and non-tuberculous pulmonary diseases than in control subjects. The mean serum ADA activity in the patients' group was 35.5±6.93 u/l as compared to 16.20±2.85 u/l in control group, showing a highly significant (P≪0.001) difference. ADA activity was highest in tuberculous pleuropulmonary diseases. The pleural fluid ADA activity was higher in pyogenic pleural effusion than in tuberculous pleural effusion.

Combination of adenosine deaminase activity and polymerase chain reaction in bronchoalveolar lavage fluid in the diagnosis of smear-negative active pulmonary tuberculosis

BACKGROUND

Some studies have assessed the diagnostic value of adenosine deaminase (ADA) activity in bronchoalveolar lavage fluid (BALF) in the diagnosis of pulmonary tuberculosis (TB). However, a conclusion has not been reached due to the limited number of patients with various pulmonary diseases used as comparators. The objective of this study was to evaluate the efficacy of BALF ADA activity and TB PCR assay for diagnosing pulmonary TB.

METHODS

BAL samples from 424 patients with acid-fast bacillus-negative sputum smears who underwent bronchoscopy for diagnostic evaluations of pulmonary diseases, were prospectively analyzed for ADA activity and TB PCR.

RESULTS

The median ADA activity of TB cases was significantly different from that of patients with solid tumor without endobronchial obstruction (p<0.001), inactive TB (p=0.04), and other (p=0.038), while this was not the case for the other pulmonary diseases. A cutoff BALF ADA activity of ≥3 U/l provided a sensitivity of 58.7% and specificity of 81.8% to differentiate TB from solid tumor without endobronchial obstruction. The sensitivity of TB PCR in BALF was 28.1% with a specificity of 99.0%. The area under the receiver operating characteristic (ROC) curve to differentiate TB from solid tumor without endobronchial obstruction was significantly higher for the combination of ADA activity ≥3 U/l and TB PCR (0.77) than for ADA activity ≥3 U/l alone (0.70, p<0.001) or for TB PCR alone (0.64, p<0.001). The sensitivity of the combination of ADA activity ≥3 U/l and TB PCR was 72.7% and the specificity was 81.8%. In TB cases, a greater radiographic extent of disease was associated with a higher median ADA activity (p=0.017).

CONCLUSIONS

BALF ADA had limited value in differentiating pulmonary TB from some other pulmonary diseases. To differentiate TB from solid tumor without endobronchial obstruction, a combination of BALF ADA and TB PCR had marked additive diagnostic value.